1. Field of the Invention
The present invention relates to a method for fabricating a semiconductor device, and in particular, to a method for fabricating a non-volatile memory.
2. Description of Related Art
A non-volatile memory is able to retain the stored data even when the electrical power is off. As a result, many electronic products have such memories to provide normal operations when booted. In particular, a flash memory allows multiple data writing, reading, and erasing operations. With these advantages, the flash memory has become one of the most widely adopted memory devices in personal computers and electronic equipments.
The floating gate of the flash memory is usually formed of a polysilicon layer by a chemical vapor deposition (CVD) process with in situ doping. However, the dopant loss of the floating gate occurs during the high-temperature subsequent processes. As a result, the conductivity of the floating gate is reduced and thus leading depletion issue, reliability issue, programming/erase distribution issue, or endurance issue.